I've not seen this gentleman's work but I did find out the hard way that there are a few questions to ask of a barrel browner that might be helpful to sort out before the work begins.
1. Do you guarantee a particular loss of wall thickness with your process or do you measure the walls before and after, documenting both?
2. Do you polish the barrel flats after browning, or leave them browned?
3. Do you remove the bead before browning so as to get a consistent finish, Or do you leave it on with a resulting slight inconsistency of finish where carding wasn't able to get into the area near the bead?
4. What color is the finishing process in the last step? (if not black and white) Will a coating occur to make a more brown or plum color?
5. Are all exposed surfaces of the breech face polished, or left browned?
Again, I don't know the person being referenced in this post but I wish I had gone over the above 5 questions before I had work done by a "noted" barrel browner. Had I known I needed to specify certain details, I surely would have.
